Mankind has been genetically modifying plants from the day selections were first made from among wild races. But, the scientific development of new varieties based on an understanding of genetic principals began only in the 1900s. Great progress has been made in understanding the workings of genes after the discovery of the structure of DNA. These advances made possible conventional breeding programs that have contributed more to cotton plant improvement than any other plant science. Now, new advances in biotechnology are making it possible to develop plants that contain genes they could not obtain by sexual means.These advances hold open the possibility of great new opportunities in cotton plant development, as well as new concerns about risks to human health and the environment, which for cotton have been shown to be unfounded so far.
Molecular techniques, known as "recombinant DNA technology", are now available to isolate genes from plants, insects, animals, and microorganisms and insert them into other organisms. The application of these biotechnology techniques to produce genetically engineered (GE) cotton plants started about two decades ago, and the first GE cotton was planted on a commercial scale in 1996/97 in Australia and the USA. Currently, two types of genetically engineered cottons are available for commercial cultivation, cotton resistant to bollworms, know as Bt cotton, and herbicide-tolerant cotton. Since its introduction in 1996, GE cotton has been one of the most rapidly adopted technologies ever. An estimated 12% of world cotton area was planted to genetically engineered cotton in 1999/2000 in Argentina, Australia, China (Mainland), Mexico, South Africa and the USA. Many other countries, in all cotton producing regions of the world, are experimenting with GE cotton varieties, and the planted area devoted to GE will likely expand.
The primary benefits from using GE cotton include reduced insecticide use and lower production costs, improved yields, lower farming risks and increased opportunities to grow cotton in areas of severe pest infestation. Secondary benefits include higher populations of beneficial insects and wildlife in cotton fields, reduced pesticide runoff and air pollution, improved farm worker and neighbor safety, reductions in labor and fuel use, and improved soil quality.
The impacts of GE cotton on human health and the environment have been investigated. Regulatory agencies and academies of science in Argentina, Australia, Canada, China (Mainland), Japan, Mexico, South Africa and the USA have concluded that GE cotton does not pose any different risks to human or animal health than non-GE cotton. Regulatory agencies have also determined that the potential for cross-pollination between GE cotton varieties and other plants is very small. Commercial cotton varieties are not sexually compatible with most wild cotton varieties, wild cottons do not grow in regions where cotton is produced commercially, and there are no identified plant species outside the cotton family that are sexually compatible with cultivated cotton.
One of the most widespread concerns about the use of GE cotton is that pests will develop resistance to the toxin produced by the Bt gene. It is almost universally agreed that resistance will develop eventually, but all participants in the cotton industry, especially the planting seed companies marketing GE products, have a vested interest in delaying the development of resistance. Consequently, measures are being taken to prevent the monocropping of GE cotton varieties, a practice that would lead to the development of resistant insect populations. Other resistance management strategies are being employed and research is also ongoing to produce new GE varieties expressing different genes.
The application of GE technology in cotton is not limited to the development of insect resistance and herbicide tolerance. Genetic engineering may also be used to produce drought-resistant varieties, thus expanding the reach of cotton production. Alternatively, desirable characteristics might be added to cotton, such as increased fineness, higher strength, increased flame resistance, improved wrinkle recovery in fabric, or desirable colors, potentially reducing the need for chemical dyes. Many other uses of GE technology have yet to be thought of.
GE technology could have beneficial applications beyond imagination. The technology is a strong additional tool in the hands of breeders for crop improvement. However, there are some people that believe that there is also a potential for the technology to be misused with unforeseen consequences. GE technology is new and must be watched and utilized carefully.
The International Cotton Advisory Committee (ICAC) keeps cotton researchers in member countries appraised of developments in the field of biotechnology. ICAC has published a number of technical reports on biotechnology and genetic engineering of cotton. ICAC published a detailed review article on Biotechnology of Cotton in 1991. Since then a number of reports on the current status and possible consequences have been published in its technical journal THE ICAC RECORDER. Lately, the ICAC has had an Expert Panel put together a report on Biotechnology in cotton and has launched another review article, Biotechnology in Cotton Research and Production, which will be available by end of this year or early 2001. While the first review article dealt with basic concept and technologies, the new article will focus on practical aspects and utilization of this technology.